Problem Display
PID: 162199 (5K2/8/8/1R1Q2N1/6pk/7N/8/8 w - - 0 1)

Lincoln, Robert A

4/5 Comm., The Problemist, 2015/II

5K2/8/8/1R1Q2N1/6pk/7N/8/8

#2

5 + 2


145 StrateGems 2017
5454 Near Snap 2022

SOLUTION


  • SOUND
  • Tries
    • 1.Qh1?
      • 1...Kh5
        • 2.Sf4#
      • 1...gxh3
        • 2.Qxh3#
      • 1...g3
        • 2.Sf2#
      • 1...Kg3!
    • 1.Qe4?
      • 1...Kh5
        • 2.Qh7#
      • 1...Kg3!
    • 1.Qe6?
      • 1...Kh5
        • 2.Sf3#
      • 1...gxh3
        • 2.Qxh3#
      • 1...g3
        • 2.Sf3#
      • 1...Kg3!
    • 1.Qf7?
      • 1...Kg3
        • 2.Qf2#
      • 1...g3
        • 2.Rb4#
      • 1...gxh3!
    • 1.Qd3?
      • 1...Kh5
        • 2.Qh7#
      • 1...gxh3
        • 2.Qxh3#
      • 1...g3!
    • 1.Qd4?
      • 1...Kg3
        • 2.Qf2#
      • 1...Kh5!
    • 1.Qd7?
      • 1...Kh5
        • 2.Qh7#
      • 1...gxh3
        • 2.Qxh3#
      • 1...g3
        • 2.Sf3#
      • 1...Kg3!
  • Keys
    • 1.Qf5!
      • 1...Kg3
        • 2.Qf2#
      • 1...Kh5
        • 2.Qh7#
      • 1...gxh3
        • 2.Qxh3#
      • 1...g3
        • 2.Sf3#

Anticipated by 75069(1994)

This is a version of 39230

FEATURES


  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 0
    • ADDED MATES = 4
    • REMOVED MATES = 0
  • Sets
  • Tries
    • Try
      • Q(C);
      • Vars
        • K(b);P-FLIGHT::QAR(C)+S(A),DCHECK
        • P(a);OGATE,P_SPINP(a),XS(A)::QAR1(C),XP(a)
        • P(a);SBLOCK::QAR(C)+S(A)
      • Refutation
        • K(b);S_FLIGHT
    • Try
      • Q(C);P_PINP(a)
      • Vars
        • K(b);N_SPINP(a),P-FLIGHT::QAR2(C)
      • Refutation
        • K(b);N_SPINP(a),S_FLIGHT
    • Try
      • Q(C);
      • Vars
        • K(b);P-FLIGHT::R(B)+S(D)
        • P(a);OGATE,XS(A)::QAR1(C),XP(a)
        • P(a);N_GUARD,SBLOCK::S(D)
      • Refutation
        • K(b);S_FLIGHT
    • Try
      • Q(C);
      • Vars
        • K(b);S_FLIGHT::QAB1(C)
        • P(a);OGATEB,SBLOCK::R(B)
      • Refutation
        • P(a);XS(A)
    • Try
      • Q(C);
      • Vars
        • K(b);P-FLIGHT::QAR2(C)
        • P(a);OGATE,XS(A)::QAR1(C),XP(a)
      • Refutation
        • P(a);
    • Try
      • Q(C);P_PINP(a)
      • Vars
        • K(b);N_SPINP(a),S_FLIGHT::QAB1(C)
      • Refutation
        • K(b);N_SPINP(a),P-FLIGHT
    • Try
      • Q(C);
      • Vars
        • K(b);P-FLIGHT::QAR2(C)
        • P(a);OGATE,XS(A)::QAR1(C),XP(a)
        • P(a);N_GUARD,SBLOCK::S(D)
      • Refutation
        • K(b);S_FLIGHT
  • Actual
    • Q(C);
    • Vars
      • K(b);S_FLIGHT::QAB1(C)
      • K(b);P-FLIGHT::QAR2(C)
      • P(a);OGATE,XS(A)::QAR1(C),XP(a)
      • P(a);N_GUARD,SBLOCK::S(D)


Developed and maintained by Brian Stephenson.
Implemented with HTML5, MySQL, Perl (with, inter alia, CGI::Simple, HTML::Template & XML::LibXML) & CSS/Javascript (jQuery, Bootstrap & DataTables).